cadrok Posted April 9, 2007 Share Posted April 9, 2007 I have a Videomate T750 Dual TV tuner card. Outdoor antenna, quad screened cable into a splitter, one side to a digtal TV the other to the tuner card. I connected the cable into the card and could not get any digital channels. I then plugged cable into the signal splitter supplied with the card and can get good analog channels but limited digital channels. The digital channels vary greatly sometimes I can get all, sometimes none. I found out by accident that if I unplug the signal splitter from the card and just have the outer screen connectors touching with no connection to the centre conductor I get all digital channels working perfectly. The digital TV works fine, the signal strength indicates about 70%. Anyone have an idea of what is happening? Link to comment Share on other sites More sharing options...
daro1503559926 Posted April 28, 2007 Share Posted April 28, 2007 The T750 has got what is refured to as a "Silicon Tuner" that bieng that the whole thing is made from silicon with no coils & other passive compents that would be required. These tuners are very senistive & are easley overloaded causing loss of digital signals. The fix would be to use an attenuator ahead of the tuner & that should fix your problem. Link to comment Share on other sites More sharing options...
alanh Posted April 29, 2007 Share Posted April 29, 2007 daro, I find it hard to believe that you can use a sampling filter at 820 MHz and get channels 0f 7 MHz. Even if this is the case you need an analog to digital converter first. This would be susceptable to any inferference from power mains, FM radio and other TV transmitters. This would be impossible. I suggest it is just a conventional tuner which is either more sensitive than most or has a poor automatic gain control. AlanH Link to comment Share on other sites More sharing options...
cadrok Posted June 2, 2007 Author Share Posted June 2, 2007 All fixed. I put an attenuator before the card and it now works perfectly on all channels. Thank you. Link to comment Share on other sites More sharing options...
Alwyn Posted August 14, 2007 Share Posted August 14, 2007 I may be having the same problem with my Videomate T220. What value attenuator should I get? Link to comment Share on other sites More sharing options...
charlesc Posted August 14, 2007 Share Posted August 14, 2007 I may be having the same problem with my Videomate T220. What value attenuator should I get? I must admit if I was inserting attenuation, I would use fixed values, and add them in series as required. Maybe read this post. Link to comment Share on other sites More sharing options...
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